net/sched/act_skbedit.c

   1 /*
   2  * Copyright (c) 2008, Intel Corporation.
   3  *
   4  * This program is free software; you can redistribute it and/or modify it
   5  * under the terms and conditions of the GNU General Public License,
   6  * version 2, as published by the Free Software Foundation.
   7  *
   8  * This program is distributed in the hope it will be useful, but WITHOUT
   9  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  10  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
  11  * more details.
  12  *
  13  * You should have received a copy of the GNU General Public License along with
  14  * this program; if not, see <http://www.gnu.org/licenses/>.
  15  *
  16  * Author: Alexander Duyck <alexander.h.duyck@intel.com>
  17  */
  18
  19 #include <linux/module.h>
  20 #include <linux/init.h>
  21 #include <linux/kernel.h>
  22 #include <linux/skbuff.h>
  23 #include <linux/rtnetlink.h>
  24 #include <net/netlink.h>
  25 #include <net/pkt_sched.h>
  26
  27 #include <linux/tc_act/tc_skbedit.h>
  28 #include <net/tc_act/tc_skbedit.h>
  29
  30 #define SKBEDIT_TAB_MASK     15
  31 static struct tcf_common *tcf_skbedit_ht[SKBEDIT_TAB_MASK + 1];
  32 static u32 skbedit_idx_gen;
  33 static DEFINE_RWLOCK(skbedit_lock);
  34
  35 static struct tcf_hashinfo skbedit_hash_info = {
  36         .htab   =       tcf_skbedit_ht,
  37         .hmask  =       SKBEDIT_TAB_MASK,
  38         .lock   =       &skbedit_lock,
  39 };
  40
  41 static int tcf_skbedit(struct sk_buff *skb, const struct tc_action *a,
  42                        struct tcf_result *res)
  43 {
  44         struct tcf_skbedit *d = a->priv;
  45
  46         spin_lock(&d->tcf_lock);
  47         d->tcf_tm.lastuse = jiffies;
  48         bstats_update(&d->tcf_bstats, skb);
  49
  50         if (d->flags & SKBEDIT_F_PRIORITY)
  51                 skb->priority = d->priority;
  52         if (d->flags & SKBEDIT_F_QUEUE_MAPPING &&
  53             skb->dev->real_num_tx_queues > d->queue_mapping)
  54                 skb_set_queue_mapping(skb, d->queue_mapping);
  55         if (d->flags & SKBEDIT_F_MARK)
  56                 skb->mark = d->mark;
  57
  58         spin_unlock(&d->tcf_lock);
  59         return d->tcf_action;
  60 }
  61
  62 static const struct nla_policy skbedit_policy[TCA_SKBEDIT_MAX + 1] = {
  63         [TCA_SKBEDIT_PARMS]             = { .len = sizeof(struct tc_skbedit) },
  64         [TCA_SKBEDIT_PRIORITY]          = { .len = sizeof(u32) },
  65         [TCA_SKBEDIT_QUEUE_MAPPING]     = { .len = sizeof(u16) },
  66         [TCA_SKBEDIT_MARK]              = { .len = sizeof(u32) },
  67 };
  68
  69 static int tcf_skbedit_init(struct net *net, struct nlattr *nla,
  70                             struct nlattr *est, struct tc_action *a,
  71                             int ovr, int bind)
  72 {
  73         struct nlattr *tb[TCA_SKBEDIT_MAX + 1];
  74         struct tc_skbedit *parm;
  75         struct tcf_skbedit *d;
  76         struct tcf_common *pc;
  77         u32 flags = 0, *priority = NULL, *mark = NULL;
  78         u16 *queue_mapping = NULL;
  79         int ret = 0, err;
  80
  81         if (nla == NULL)
  82                 return -EINVAL;
  83
  84         err = nla_parse_nested(tb, TCA_SKBEDIT_MAX, nla, skbedit_policy);
  85         if (err < 0)
  86                 return err;
  87
  88         if (tb[TCA_SKBEDIT_PARMS] == NULL)
  89                 return -EINVAL;
  90
  91         if (tb[TCA_SKBEDIT_PRIORITY] != NULL) {
  92                 flags |= SKBEDIT_F_PRIORITY;
  93                 priority = nla_data(tb[TCA_SKBEDIT_PRIORITY]);
  94         }
  95
  96         if (tb[TCA_SKBEDIT_QUEUE_MAPPING] != NULL) {
  97                 flags |= SKBEDIT_F_QUEUE_MAPPING;
  98                 queue_mapping = nla_data(tb[TCA_SKBEDIT_QUEUE_MAPPING]);
  99         }
 100
 101         if (tb[TCA_SKBEDIT_MARK] != NULL) {
 102                 flags |= SKBEDIT_F_MARK;
 103                 mark = nla_data(tb[TCA_SKBEDIT_MARK]);
 104         }
 105
 106         if (!flags)
 107                 return -EINVAL;
 108
 109         parm = nla_data(tb[TCA_SKBEDIT_PARMS]);
 110
 111         pc = tcf_hash_check(parm->index, a, bind, &skbedit_hash_info);
 112         if (!pc) {
 113                 pc = tcf_hash_create(parm->index, est, a, sizeof(*d), bind,
 114                                      &skbedit_idx_gen, &skbedit_hash_info);
 115                 if (IS_ERR(pc))
 116                         return PTR_ERR(pc);
 117
 118                 d = to_skbedit(pc);
 119                 ret = ACT_P_CREATED;
 120         } else {
 121                 d = to_skbedit(pc);
 122                 if (!ovr) {
 123                         tcf_hash_release(pc, bind, &skbedit_hash_info);
 124                         return -EEXIST;
 125                 }
 126         }
 127
 128         spin_lock_bh(&d->tcf_lock);
 129
 130         d->flags = flags;
 131         if (flags & SKBEDIT_F_PRIORITY)
 132                 d->priority = *priority;
 133         if (flags & SKBEDIT_F_QUEUE_MAPPING)
 134                 d->queue_mapping = *queue_mapping;
 135         if (flags & SKBEDIT_F_MARK)
 136                 d->mark = *mark;
 137
 138         d->tcf_action = parm->action;
 139
 140         spin_unlock_bh(&d->tcf_lock);
 141
 142         if (ret == ACT_P_CREATED)
 143                 tcf_hash_insert(pc, &skbedit_hash_info);
 144         return ret;
 145 }
 146
 147 static int tcf_skbedit_cleanup(struct tc_action *a, int bind)
 148 {
 149         struct tcf_skbedit *d = a->priv;
 150
 151         if (d)
 152                 return tcf_hash_release(&d->common, bind, &skbedit_hash_info);
 153         return 0;
 154 }
 155
 156 static int tcf_skbedit_dump(struct sk_buff *skb, struct tc_action *a,
 157                             int bind, int ref)
 158 {
 159         unsigned char *b = skb_tail_pointer(skb);
 160         struct tcf_skbedit *d = a->priv;
 161         struct tc_skbedit opt = {
 162                 .index   = d->tcf_index,
 163                 .refcnt  = d->tcf_refcnt - ref,
 164                 .bindcnt = d->tcf_bindcnt - bind,
 165                 .action  = d->tcf_action,
 166         };
 167         struct tcf_t t;
 168
 169         if (nla_put(skb, TCA_SKBEDIT_PARMS, sizeof(opt), &opt))
 170                 goto nla_put_failure;
 171         if ((d->flags & SKBEDIT_F_PRIORITY) &&
 172             nla_put(skb, TCA_SKBEDIT_PRIORITY, sizeof(d->priority),
 173                     &d->priority))
 174                 goto nla_put_failure;
 175         if ((d->flags & SKBEDIT_F_QUEUE_MAPPING) &&
 176             nla_put(skb, TCA_SKBEDIT_QUEUE_MAPPING,
 177                     sizeof(d->queue_mapping), &d->queue_mapping))
 178                 goto nla_put_failure;
 179         if ((d->flags & SKBEDIT_F_MARK) &&
 180             nla_put(skb, TCA_SKBEDIT_MARK, sizeof(d->mark),
 181                     &d->mark))
 182                 goto nla_put_failure;
 183         t.install = jiffies_to_clock_t(jiffies - d->tcf_tm.install);
 184         t.lastuse = jiffies_to_clock_t(jiffies - d->tcf_tm.lastuse);
 185         t.expires = jiffies_to_clock_t(d->tcf_tm.expires);
 186         if (nla_put(skb, TCA_SKBEDIT_TM, sizeof(t), &t))
 187                 goto nla_put_failure;
 188         return skb->len;
 189
 190 nla_put_failure:
 191         nlmsg_trim(skb, b);
 192         return -1;
 193 }
 194
 195 static struct tc_action_ops act_skbedit_ops = {
 196         .kind           =       "skbedit",
 197         .hinfo          =       &skbedit_hash_info,
 198         .type           =       TCA_ACT_SKBEDIT,
 199         .capab          =       TCA_CAP_NONE,
 200         .owner          =       THIS_MODULE,
 201         .act            =       tcf_skbedit,
 202         .dump           =       tcf_skbedit_dump,
 203         .cleanup        =       tcf_skbedit_cleanup,
 204         .init           =       tcf_skbedit_init,
 205 };
 206
 207 MODULE_AUTHOR("Alexander Duyck, <alexander.h.duyck@intel.com>");
 208 MODULE_DESCRIPTION("SKB Editing");
 209 MODULE_LICENSE("GPL");
 210
 211 static int __init skbedit_init_module(void)
 212 {
 213         return tcf_register_action(&act_skbedit_ops);
 214 }
 215
 216 static void __exit skbedit_cleanup_module(void)
 217 {
 218         tcf_unregister_action(&act_skbedit_ops);
 219 }
 220
 221 module_init(skbedit_init_module);
 222 module_exit(skbedit_cleanup_module);